Slice of Life moments are the series's biggest strength. The dude's a blessing on the family he meets and the friends he makes. Sometimes it feels like he's the side-character in the family. I think he deserves to have his own arcs, development and possibly romance (hint hint the girl who's trying to win his heart but nothing happened between them yet).
The series started somewhat going downhill after chapter 20.
The fights are terrible, villains are comically bad. He's OP asf so fights are done very quickly. Pacing isn't good, structure of the chapter isn't setup properly, story starts out of nowhere without any explanation or introducing a new character without any setup.
MC doesn't want to stand out and doesn't (most of the time). There are a million ways he could've revealed himself in the modern world accidentally to people but author doesn't really go into it, he's just too OP for that. Obviously he has to reveal his identity to some people in-power so it happens but it's kinda stupid. One arc ago he was using some magic/qi bullshit to hide his face from the lone villains but he didn't this time with the good guy also being there, just used a face-mask so that the character can recognize them later lol.
Technological advancements seem the standard-fare stuff you see in Gate-type manhwa. I'll take this opportunity to point out a flaw in the series. He gets an inventory tattoo thingy he can apply from his disciple (oh yeah I haven't talked about disciple yet). The inventory's size depends on owner's power so MC's very huge and what does he do to test it? Build a modern-architecture building. I get that it's to showcase how complex stuff can be done easily and it depends on the owner's power but MC also could've built something from his past life. You know what? It happens later in the series, there are many interesting moments that could've been so much more or interesting ones happen.
Let's talk about the girl he saves at the beginning, that girl's got to be traumatized after getting into so much incidents. Also too many coincidences where MC just happens open to be near the bad guys. At the moment of reading, she just got a bodyguard who might help with such incidents fortunately but as I said in the last paragraph it's not done well. Also she's shaping up to be a character with great powers so I wonder how the author will handle it in future.
Talking about the bad guys again, there seems to be an overarching plot of Demonic Cult people from his past life responsible for the gates and evil stuff happening everywhere. They're trying to harness despair from people to gain power, standard bad guy stuff, which at this point it doesn't feel really interesting for me. There's one bad guy who kinda stands out at least from others.
That said, I'm still binging it. I'd recommend you try it out if you just wanna read a wholesome SoL life if you're burnt out from other ones.